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Diffstat (limited to 'arch/arm/mm/ioremap.c')
-rw-r--r--arch/arm/mm/ioremap.c119
1 files changed, 75 insertions, 44 deletions
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index bdb248c4f55..80632e8d753 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -36,12 +36,6 @@
#include <asm/mach/map.h>
#include "mm.h"
-/*
- * Used by ioremap() and iounmap() code to mark (super)section-mapped
- * I/O regions in vm_struct->flags field.
- */
-#define VM_ARM_SECTION_MAPPING 0x80000000
-
int ioremap_page(unsigned long virt, unsigned long phys,
const struct mem_type *mtype)
{
@@ -64,7 +58,7 @@ void __check_kvm_seq(struct mm_struct *mm)
} while (seq != init_mm.context.kvm_seq);
}
-#ifndef CONFIG_SMP
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
/*
* Section support is unsafe on SMP - If you iounmap and ioremap a region,
* the other CPUs will not see this change until their next context switch.
@@ -79,13 +73,16 @@ static void unmap_area_sections(unsigned long virt, unsigned long size)
{
unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmdp;
flush_cache_vunmap(addr, end);
pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmdp = pmd_offset(pud, addr);
do {
- pmd_t pmd, *pmdp = pmd_offset(pgd, addr);
+ pmd_t pmd = *pmdp;
- pmd = *pmdp;
if (!pmd_none(pmd)) {
/*
* Clear the PMD from the page table, and
@@ -104,8 +101,8 @@ static void unmap_area_sections(unsigned long virt, unsigned long size)
pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
}
- addr += PGDIR_SIZE;
- pgd++;
+ addr += PMD_SIZE;
+ pmdp += 2;
} while (addr < end);
/*
@@ -124,6 +121,8 @@ remap_area_sections(unsigned long virt, unsigned long pfn,
{
unsigned long addr = virt, end = virt + size;
pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
/*
* Remove and free any PTE-based mapping, and
@@ -132,17 +131,17 @@ remap_area_sections(unsigned long virt, unsigned long pfn,
unmap_area_sections(virt, size);
pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
do {
- pmd_t *pmd = pmd_offset(pgd, addr);
-
pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
pfn += SZ_1M >> PAGE_SHIFT;
pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
pfn += SZ_1M >> PAGE_SHIFT;
flush_pmd_entry(pmd);
- addr += PGDIR_SIZE;
- pgd++;
+ addr += PMD_SIZE;
+ pmd += 2;
} while (addr < end);
return 0;
@@ -154,6 +153,8 @@ remap_area_supersections(unsigned long virt, unsigned long pfn,
{
unsigned long addr = virt, end = virt + size;
pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
/*
* Remove and free any PTE-based mapping, and
@@ -162,6 +163,8 @@ remap_area_supersections(unsigned long virt, unsigned long pfn,
unmap_area_sections(virt, size);
pgd = pgd_offset_k(virt);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
do {
unsigned long super_pmd_val, i;
@@ -170,14 +173,12 @@ remap_area_supersections(unsigned long virt, unsigned long pfn,
super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
for (i = 0; i < 8; i++) {
- pmd_t *pmd = pmd_offset(pgd, addr);
-
pmd[0] = __pmd(super_pmd_val);
pmd[1] = __pmd(super_pmd_val);
flush_pmd_entry(pmd);
- addr += PGDIR_SIZE;
- pgd++;
+ addr += PMD_SIZE;
+ pmd += 2;
}
pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
@@ -195,17 +196,13 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
unsigned long addr;
struct vm_struct * area;
+#ifndef CONFIG_ARM_LPAE
/*
* High mappings must be supersection aligned
*/
if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK))
return NULL;
-
- /*
- * Don't allow RAM to be mapped - this causes problems with ARMv6+
- */
- if (WARN_ON(pfn_valid(pfn)))
- return NULL;
+#endif
type = get_mem_type(mtype);
if (!type)
@@ -216,12 +213,40 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
*/
size = PAGE_ALIGN(offset + size);
+ /*
+ * Try to reuse one of the static mapping whenever possible.
+ */
+ read_lock(&vmlist_lock);
+ for (area = vmlist; area; area = area->next) {
+ if (!size || (sizeof(phys_addr_t) == 4 && pfn >= 0x100000))
+ break;
+ if (!(area->flags & VM_ARM_STATIC_MAPPING))
+ continue;
+ if ((area->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
+ continue;
+ if (__phys_to_pfn(area->phys_addr) > pfn ||
+ __pfn_to_phys(pfn) + size-1 > area->phys_addr + area->size-1)
+ continue;
+ /* we can drop the lock here as we know *area is static */
+ read_unlock(&vmlist_lock);
+ addr = (unsigned long)area->addr;
+ addr += __pfn_to_phys(pfn) - area->phys_addr;
+ return (void __iomem *) (offset + addr);
+ }
+ read_unlock(&vmlist_lock);
+
+ /*
+ * Don't allow RAM to be mapped - this causes problems with ARMv6+
+ */
+ if (WARN_ON(pfn_valid(pfn)))
+ return NULL;
+
area = get_vm_area_caller(size, VM_IOREMAP, caller);
if (!area)
return NULL;
addr = (unsigned long)area->addr;
-#ifndef CONFIG_SMP
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
if (DOMAIN_IO == 0 &&
(((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
cpu_is_xsc3()) && pfn >= 0x100000 &&
@@ -313,28 +338,34 @@ __arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached)
void __iounmap(volatile void __iomem *io_addr)
{
void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
-#ifndef CONFIG_SMP
- struct vm_struct **p, *tmp;
+ struct vm_struct *vm;
- /*
- * If this is a section based mapping we need to handle it
- * specially as the VM subsystem does not know how to handle
- * such a beast. We need the lock here b/c we need to clear
- * all the mappings before the area can be reclaimed
- * by someone else.
- */
- write_lock(&vmlist_lock);
- for (p = &vmlist ; (tmp = *p) ; p = &tmp->next) {
- if ((tmp->flags & VM_IOREMAP) && (tmp->addr == addr)) {
- if (tmp->flags & VM_ARM_SECTION_MAPPING) {
- unmap_area_sections((unsigned long)tmp->addr,
- tmp->size);
- }
+ read_lock(&vmlist_lock);
+ for (vm = vmlist; vm; vm = vm->next) {
+ if (vm->addr > addr)
+ break;
+ if (!(vm->flags & VM_IOREMAP))
+ continue;
+ /* If this is a static mapping we must leave it alone */
+ if ((vm->flags & VM_ARM_STATIC_MAPPING) &&
+ (vm->addr <= addr) && (vm->addr + vm->size > addr)) {
+ read_unlock(&vmlist_lock);
+ return;
+ }
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
+ /*
+ * If this is a section based mapping we need to handle it
+ * specially as the VM subsystem does not know how to handle
+ * such a beast.
+ */
+ if ((vm->addr == addr) &&
+ (vm->flags & VM_ARM_SECTION_MAPPING)) {
+ unmap_area_sections((unsigned long)vm->addr, vm->size);
break;
}
- }
- write_unlock(&vmlist_lock);
#endif
+ }
+ read_unlock(&vmlist_lock);
vunmap(addr);
}